Photographic objective



SEARCH ROOM 'flwwf )www5 Jan'. 12, 1960 H. ElsMANN Erm.

PHoToGRAPHIc OBJECTIVE Az o {L4- Filed Feb. 1s, 1959 United States Patent I A n/r-the individual surface refractive powers, s-the focal intercept, and f-the focal length.

In the appended figure of the illustration a schematic representation of the lens design of the said objectives is given.

The tabular values given refer to a focal length of f=1.00. The aperture ratio in both embodiments of the objective is 1:2.

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Patented Jan. 12, 1960 Table I 2920528 l Lenses Radil Apical n v PHoToGRAPmc oBJEc'nvE 5 separati@ Helmut Eismann, Heidenheim (Brenz), and Gnther r1=|0. 99395 Lange, Konigsbronn, Germany, assignors to Carl Zeiss, LI r 3 09812 F0-11615 1-71300 53-89 Heidenheim (Brenz): Wrttembergs Gelmany Ln l +3'28173 d,=0,06050 1,59551 39,20

f3= A Application February 16, 1959, Serial No. 793,634 n=+0 35520 dr=0.00302 claims priority, application Germany vFebruary' 20, 195s L mmm TE' W27 m3 2 Claims' (Cl. 88-57) L rre-0.30759 diam 1 78470 -26 lo l Llv u 'F4-4.25209 zd-0. 14779 1.74400 4490 The invention concerns high-aperture photographic obv rr=0. 41018 7- jectives consisting of four members more particularly of N=+M0194 13:000302 two inner meniscus-shaped dispersive members which Lvl de=0.11494 1.74400 44.90 turn their concave sides towards each other and enclose m- O'Sgm 37:0 8022 the diaphragm, and of two external collective members wherein the second and the fourth members are un- Ll L bein thelenses. cemented single lenses while the rst and the third mem- ,.11 n' rlgrfjeinggthe radii; bers. are memscus'shaped compound membefs which d, dg being the thicknesses and air separation of the consist each of two lenses of opposed refractive power lenses. cemented together wherein the dispersive lens is in each I I nVI being the refractive indices. case turned towards the diaphragm. (Cf. Brit. pat. spec. 48o 643) U s A Pai Spee 2 74s 656) I ""1 bmg the Abbe numbers b'thbkfllhd Basis of the invention 1s the task to create objectives of bleeillgg th gal lgthefgttleagbjecve the aforesaid designin which the focal intercept amounts to at least 70% of the focal length. Table Il The objectives according to the invention have a focal intercept of the aforesaid kind and show the following Lenses Radii Apical n v characteristics: separations O.62-f r4+|rs| 1.00-f ri=+0. 92627 0.45f r,||r,1 0.75f 35 Lr 2: 3 05836 deo-11632 *1-11300 58-89 0.42f d4+d5|d6+dq 0.65f Ln '+4 '13749 dr=0.06o58 1. 59551 39.20 0.15-f d, 0.30-f f3+0 37m 3:0'00303 v Lm n- 0'27852 dr=0.1126s 1.60892 44. 9s

r L m mv 40 s o 31704 dr=0.1s781 v r0=- L I d =0.04s47 1.78470 20.10 LIv TFH" 25829 iu 0 1332s v1 74400 44 90 2.0 10.0 v rip-0.41674 (11"0'00303 8: 3. 76799 Lvr n dr=0.09693 1.73520 41,00 Herein as well as in the two appended Tables I and II fw=-0-93294 0 7585 in which numerical values for two embodiments of obdi t th v ntion are ven there are is'vildagor ng o e m e g1 LI.. LVI bemgthe lenses;

' 5o r1 rm beingthe radii;l L-ttie leises, `d1 ds being the thicknesses and air separation of the rera u, lenses; d-the ap1a1eparatwne nI nv: being the refractive indices; n-the l'fraCtlVe lndlCeS, u! uw being the Abbe-v-numbers; v-the Abbe numbers, s being the back focal length; and

f being the focal length of the objective.

We claim: 1. A high-aperture photographic objective consisting of four members more particularly of two inner meniscusv shaped dispersive members which turn their concave sides towards each other and enclose the diaphragm and of two outer collective mem ers w erein e seco d and the fourth members are uncemented single lenses while the irst and the third members are meniscus-shaped compound members which consist each of'two lenses of opposed refractive powers cemented together wherein the dispersive lens is in each case turned towards the diaphragm characterized in that the following characteristics are simultaneously satised:

and in that its constructional data coincide with the values taken from the appended table in so far that every surface refractive power (An/r) lies within a range of |:0.35/jc and every apical separation (d) lies within a range of 10.07 f on either side of the corresponding value andl in that its constructional data coincide with the values taken from the appended table in so far that every surface refractive power (An/r) lies within a range of nl 5 v1 vvI being the Abbe-v-numbers; s' being the back focal length; and

f being the focal length of the objective.

2. A high-aperture photographic objective consistingv of four members more particularly of twol inner meniscusshaped dispersive members which turn their concave sides towards each other and enclose the diaphragm and of two outer collective members wherein ythe second and the fourth members are uncemented single lenses while the indicated in the appended table. 10.35# and every apical separation (d) lies within a Lenses Radil Apical Separan v An/r tions I r 0.99395- +0.717340/J L1 f dr=0.11015f 1. 71300 53.29

n =3.09s12.f +0. 037023/1 Ln d,=0.00050f 1.59551 39.20

u=+a2s17af d o 00302! 0.181402/1 n =+0.35590f "q +1.893s47/f Lm d1=0.11270-f 1.07270 37.23

n =+0.25250.f -a 502091/f d1=0.2s703f L n =-0. 30759-1' d o f 1 78470 2Mo '-2.551107/1 w r1=+4.25209.f l 0.000572/l Lv d1=0.14779f 1.74400 44.90

n =0.41o18f +1. 8138291] d9=0.00302.f n =+3.40194.f +0. 21s099/f Lw d1=0.11494-f 1:74400 44.90

rlp-0.885844 +0.sa9s77/f y .3'=0.s0z2f LI LVI being the lenses; range of 10.0%] on either side of the corresponding r1 rm being the radii; value indicated in the appended table.

Lenses Radli Apical Separa- 71 u An/r r .92027- 7697 L, l +0, 'f d1=0.11032f 1.71300 53.89 +o wf n =3. 05830-1 +0. 038410 1011--..' d4=0.05058-f 1.59551 39.90

n =+4. 137494 0.143930/1 40 371411' Fo'oosoaf +1s0102s/f Lm n l d1=0.1120sf 1.001102 44.08

n =0.27a52f n f 2.401095/f 0 31704)' 15:0'18781'] 2.4750821; f =1 Lw dt=0.04847-f 1. 78470 2s. 10

f1 ==+4. 25829-1' 0. 009558v Lv d1=0.1332s.f 1.74400 44.90

n=0.41074f +1.7s5zs0/f +3 707991' 13:0'003034 +0 195117/f T Lvl. .o 932%! 1n-0.090934 1. 73520 41.00 +0 7 f 1 a'=0.75a5-f d1 d, being the thicknesses andair separation of the L; LVI b eing thelens'es;

lenses; A r1 -rm bemg the radn; f

nv; being the refractive indices; d1 v. d, being the thicknesses and a1r separation of the rst and the third members are meniscus-shaped com- 75 2,748,656

lenses:` n! nv; being the refractive indices; v1 vv; being the Abbe-v-numbers; s being the back focal length; and f being the focal length of the objective.

References Cited in the le of this patent UNITED STATES PATENTS 2,171,540 Beren sept. 5. 1939 y2,649,023 Tronnier Aug. 18, 1953 Berger et al. June 5, `1956 

